Jonny and Laser start with d4, Nirvana with e4. The other engines tried both options.

Opening by first ECO letter
A - 1 (3.6%), no English, Dutch or Reti
B - 3 (10.7%), all Caro-Kann, no Sicilian
C - 7 (25%), of which 6 are French Exchange, and one Giuoco Piano, no Ruy Lopez
D - 13 (46.4%), 9 of which are QGD variants.
E - 4 (14.3%), 3 of which are Nimzo-Indian